1Grate frozen butter using a box grater into a large mixing bowl. Add ground beef and mix until butter is well incorporated. Form 4 equal-sized patties and season with salt and pepper.
2Grate frozen butter using a box grater into a large mixing bowl. Add ground beef and mix until butter is well incorporated. Form 4 equal-sized patties and season with salt and pepper.
3Grate frozen butter using a box grater into a large mixing bowl. Add ground beef and mix until butter is well incorporated. Form 4 equal-sized patties and season with salt and pepper.
4Add rendered bacon fat or oil to a large frying pan over medium-high heat. Add patties and cook for 2-3 minutes before flipping. Add cheese and cook for another 2-3 minutes.
5Add rendered bacon fat or oil to a large frying pan over medium-high heat. Add patties and cook for 2-3 minutes before flipping. Add cheese and cook for another 2-3 minutes.
6Add rendered bacon fat or oil to a large frying pan over medium-high heat. Add patties and cook for 2-3 minutes before flipping. Add cheese and cook for another 2-3 minutes.
7Remove patties and place on a cooling rack with paper towels underneath to rest.
8Remove patties and place on a cooling rack with paper towels underneath to rest.
9Remove patties and place on a cooling rack with paper towels underneath to rest.
10Add sliced onions to the hot pan and cook for 2 minutes until softened. Deglaze with beef stock, add brown sugar and salt. Cook, stirring frequently, until onions are caramelized (about 5 minutes).
11Add sliced onions to the hot pan and cook for 2 minutes until softened. Deglaze with beef stock, add brown sugar and salt. Cook, stirring frequently, until onions are caramelized (about 5 minutes).
12Add sliced onions to the hot pan and cook for 2 minutes until softened. Deglaze with beef stock, add brown sugar and salt. Cook, stirring frequently, until onions are caramelized (about 5 minutes).
13Place burger patties on toasted buns, top with caramelized onions, and serve.
14Place burger patties on toasted buns, top with caramelized onions, and serve.
15Place burger patties on toasted buns, top with caramelized onions, and serve.